Detection of Histone H3 Ser10 phosphorylation by Western blot

I have some problems to get nice blots of phospho Histone H3 (Milipore antibody). Usually I use this extraction protocol with works quite nice and I get a good yield of Histones which I can see by staining the blot with total Histone H3 antibody.

My problem is that the phosphorylation state does not really make sense and is not reproduceable. Additionally I add NaF and Na3VO4 in the TEB Buffer to avoid dephosphorylation. Is the acid interfering with the activity of these inhibitors?Does anybody know a nice protocol which allows me to detect this phosphorylation by western blot?